%% You should probably cite rfc3161 instead of this I-D.
@techreport{ietf-pkix-time-stamp-15,
    number =    {draft-ietf-pkix-time-stamp-15},
    type =      {Internet-Draft},
    institution =   {Internet Engineering Task Force},
    publisher = {Internet Engineering Task Force},
    note =      {Work in Progress},
    url =       {https://datatracker.ietf.org/doc/draft-ietf-pkix-time-stamp/15/},
    author =    {Robert Zuccherato and Patrick Cain and Dr. Carlisle Adams and Denis Pinkas},
    title =     {{Internet X.509 Public Key Infrastructure Time-Stamp Protocol (TSP)}},
    pagetotal = 26,
    year =      2001,
    month =     may,
    day =       25,
    abstract =  {This document describes the format of a request sent to a Time Stamping Authority (TSA) and of the response that is returned. It also establishes several security-relevant requirements for TSA operation, with regards to processing requests to generate responses. {[}STANDARDS-TRACK{]}},
}